Network slicing is a new concept that applies to both Long Term Evolution (LTE) and future fifth generation (5G) radio access technology (RAT) (denoted NX herein). In network slicing logically separated partitions of a network are created, wherein the partitions address different business purposes. These “network slices” may be logically separated to a degree such as to be regarded and managed as networks of their own. The logical network slices may enable operators to provide networks on an as-a service basis and thereby meet a wide range of expected use cases.
A driving force for introducing network slicing is a desired business expansion. Such business expansion is believed to be achievable by improving a cellular operator's ability to offer connectivity services in various business areas besides the currently provided mobile communication services. Such new connectivity services may have different network characteristics, e.g. in view of performance, security, robustness and complexity.
FIG. 1 illustrates an architecture for a current working assumption which is that there will be one shared Radio Access Network (RAN) infrastructure 1 that will connect to several Evolved Packet Core (EPC) instances 2a, 2b, in particular one EPC instance per network slice (Slice 1, Slice 2). As the EPC functions are being virtualized it is assumed that the operator can instantiate a new Core Network (CN) when a new slice should be supported. A first slice (Slice 1) may for example be a Mobile Broadband slice and a second slice (Slice 2) may for example be a Machine Type Communication network slice.
In such sliced network, with communication devices 3 (in the following exemplified by User Equipment, UE) that are capable of attaching to multiple network slices, issues may arise in view of how to handle the corresponding different connections. One conceivable approach could be to duplicate the control planes and the user planes, one duplicate pair for each network slice that the UE 3 has requested. However, such approach would be costly in terms of bandwidth, in particular over the air interface. Further, the handling related to sending messages on several connections for several network slices may give complicated procedures e.g. for handling synchronization and handovers. Difficulties may also arise in view of authentication.